Method of manufacturing semiconductor integrated circuit device

ABSTRACT

A method of manufacturing a semiconductor integrated circuit device which includes a semiconductor substrate; and multiple semiconductor elements disposed on the semiconductor substrate. The semiconductor elements include an n-channel MOS transistor and a p-channel MOS transistor. The n-channel MOS transistor is covered by a tensile stress film, and the p-channel MOS transistor is covered by a compressive stress film. A dummy region, the entire surface of which is covered by a combination of the tensile stress film and the compressive stress film, is disposed on the surface of the semiconductor substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. application Ser. No.12/561,719 filed Sep. 17, 2009, which is a continuation applicationfiled under 35 U.S.C. 111(a) claiming benefit under 35 U.S.C. 120 and365(c) of PCT International Application No. PCT/JP2007/057152, filed onMar. 30, 2007, the entire contents of which are incorporated herein byreference.

FIELD

The present disclosure is broadly directed to a semiconductor device,and in particular to a semiconductor integrated circuit device includinga p-channel MOS transistor and n-channel MOS transistor having improvedoperation speeds due to stress application.

BACKGROUND

Advancements in miniaturization technology have brought about nanoscaleand ultrafast semiconductor devices having a gate length of 30 nm orless.

In such a nanoscale and ultrafast transistor, areas of channel regionsjust below gate electrodes are significantly small compared to those ina conventional semiconductor device. Accordingly, the mobility ofelectrons or holes through the channel regions is largely affected bystress applied to the channel regions. Given this factor, manyapproaches have been developed that optimize the stress applied to thechannel regions, thereby improving the operation speed of semiconductordevices.

One of conventionally proposed structures is directed to the improvementof the operation speed of an n-channel MOS transistor, and involvesforming a stress film (a typical example of such is an SiN film) havinga tensile stress in such a manner as to include the gate electrode inthe element region of the n-channel MOS transistor. In this way, theelectron mobility in the channel region just below the gate electrode isimproved.

Another conventionally proposed structure is directed to the improvementof the operation speed of a p-channel MOS transistor, and involvesforming a stress film (such as an SiN film) having a compressive stressin such a manner as to include the gate electrode in the element regionof the p-channel MOS transistor. In this way, the hole mobility in thechannel region just below the gate electrode is improved.

Furthermore, a proposed semiconductor integrated circuit device has astructure in which a stress-application n-channel MOS transistor and astress-application p-channel MOS transistor are integrated.

Such a semiconductor integrated circuit device is formed by thefollowing procedures, for example.

That is, after an n-channel MOS transistor and a p-channel MOStransistor are formed on a semiconductor substrate, the entire structureis, first, covered by a tensile stress film. Patterning is then appliedto the structure so as to selectively remove the tensile stress filmfrom a region in which the p-channel MOS transistor is formed.

Subsequently, a compressive stress film is formed on the resultantstructure in such a manner as to directly cover the p-channel MOStransistor in the region where the p-channel MOS transistor is formed,but cover the n-channel MOS transistor with the tensile stress filminterposed in between in a region where the n-channel MOS transistor isformed. Next, the compressive stress film is selectively removed fromthe region where the n-channel MOS transistor is formed.

Alternatively, the compressive stress film may be formed first, and thetensile stress film may be subsequently formed.

Patterning of the compressive stress film is performed in the regionwhere the n-channel MOS transistor is formed, and on the other hand,patterning of the tensile stress film is performed in the region wherethe p-channel MOS transistor is formed. It is therefore consideredadvantageous to use, for the patterning in each element region, an ionimplantation mask used at the time of the well formation since thiseliminates the necessity of designing a new mask pattern.

In view of this, a method of manufacturing a semiconductor integratedcircuit device proposed by Japanese Laid-Open Patent Publication No.2006-173432 involves the following procedures. That is, in thepatterning of the tensile stress film, a mask used for the wellformation in the element region of the p-channel MOS transistor isemployed so as to leave a resist pattern only in the element region ofthe n-channel MOS transistor and remove the tensile stress film from theremaining region. On the other hand, in the patterning of thecompressive stress film, a mask used for the well formation in theelement region of the n-channel MOS transistor is employed so as toexpose only the element region of the n-channel MOS transistor and,then, remove the tensile stress film only from the element region of then-channel MOS transistor while covering the remaining region with aresist pattern.

In a semiconductor integrated circuit device formed in theabove-mentioned manner, the tensile stress film is formed only in theelement region of the n-channel MOS transistor and the remaining elementregion is covered by the compressive stress film. Alternatively, thecompressive stress film is formed only in the element region of thep-channel MOS transistor and the remaining element region may be coveredby the tensile stress film.

On the other hand, the area occupancies of the re-channel MOS transistorand the p-channel MOS transistor on the semiconductor substrate varyfrom product to product. Therefore, in such semiconductor integratedcircuit devices, the area ratio between the tensile stress film and thecompressive stress film is generally different from product to product.

Etching conditions for patterning are different between the tensilestress film and the compressive stress film. Accordingly, in the casewhere the area ratio between the tensile stress film and the compressivestress film on the semiconductor substrate is different among products,the etching conditions for patterning the tensile stress film and thecompressive stress film need to be adjusted for individual products.However, it is difficult to optimize the etching conditions with respectto each product.

Recently, a business has been adopted that leases out different regionsout of the same semiconductor wafer to various customers andmanufactures semiconductor integrated circuit devices having differentspecifications according to individual requests for trial production.The above-described conventional manufacturing method cannot deal withcases like this.

SUMMARY

One aspect of the present disclosure is a semiconductor integratedcircuit device including a semiconductor substrate; and multiplesemiconductor elements disposed on the semiconductor substrate. Thesemiconductor elements include an n-channel MOS transistor and ap-channel MOS transistor. The n-channel MOS transistor is covered by atensile stress film, and the p-channel MOS transistor is covered by acompressive stress film. A dummy region, the entire surface of which iscovered by a combination of the tensile stress film and the compressivestress film, is disposed on the surface of the semiconductor substrate.

The object and advantages of the disclosure will be realized andattained by means of the elements and combinations particularly pointedout in the claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and arenot restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a process (part 1) for manufacturing a semiconductorintegrated circuit device according to the first embodiment of thepresent disclosure;

FIG. 1B illustrates a process (part 2) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 1C illustrates a process (part 3) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 1D illustrates a process (part 4) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 1E illustrates a process (part 5) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 1F illustrates a process (part 6) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 1G illustrates a process (part 7) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 1H illustrates a process (part 8) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 1I illustrates a process (part 9) for manufacturing thesemiconductor integrated circuit device according to the firstembodiment of the present disclosure;

FIG. 2 illustrates the relationship between area occupancy of a stressfilm pattern and etching rate;

FIG. 3 illustrates a structure of a semiconductor integrated circuitdevice according to a modification of the first embodiment;

FIG. 4 illustrates an example of dummy stress film patterns according tothe second embodiment of the present disclosure;

FIG. 5 illustrates an example of a dummy stress film pattern accordingto a modification of the second embodiment;

FIG. 6 illustrates an example of a semiconductor integrated circuitdevice having dummy stress film patterns;

FIG. 7 illustrates another example of the semiconductor integratedcircuit device having dummy stress film patterns; and

FIG. 8 illustrates yet another example of the semiconductor integratedcircuit device having dummy stress film patterns.

DESCRIPTION OF EMBODIMENTS First Embodiment

FIGS. 1A through 1I illustrate a method of manufacturing a semiconductorintegrated circuit device according to the first embodiment of thepresent disclosure. On the semiconductor integrated circuit device, astress-application p-channel MOS transistor and a stress-applicationn-channel MOS transistor are integrated.

With reference to FIG. 1A, on a silicon substrate 11, an n-channel MOStransistor element region 11N and a p-channel MOS transistor elementregion 11P are defined by an element isolating region 11I having ashallow trench isolation (STI) structure. In the element region 11N, ap-type impurity element is introduced to form a p-type well 11 pw, andin the element region 11P, an n-type impurity element is introduced toform an n-type well 11 nw.

Furthermore, in the state illustrated in FIG. 1A, an insulating film 12,such as a thermally-oxidized film or an SiON film, is formed over theelement regions 11N and 11P.

Next in the process illustrated in FIG. 1B, a gate electrode 13N and agate electrode 13P made of polysilicon, metal or the like are formed inthe element regions 11N and 11P, respectively, in such a manner thatgate insulating films 12N and 12P formed of the insulating film 12 aredisposed between the gate electrode 13N and the silicon substrate 11 andbetween the gate electrode 13P and the silicon substrate 11,respectively. In the element region 11N, an n-type source extensionregion 11 aN and an n-type drain extension region 11 bN are provided ona first side and a second side, respectively, of the gate electrode 13N.

Furthermore, sidewall insulating films 13 n are formed on a first and asecond sidewall surface which oppose each other across the gateelectrode 13N. In the element region 11N, an n+ type source region 11 cNand an n+ type drain region 11 dN are disposed outward from the sidewallinsulating films 13 n. On the surface of the source region 11 cN and thedrain region 11 dN, individual silicide layers 11 s are formed.

In the case where the gate electrode 13N is formed using a polysiliconpattern, a silicide layer 14N is disposed also on the gate electrode13N.

Also in the process illustrated in FIG. 1B, in the element region 11P, ap-type source extension region 11 aP and a p-type drain extension region11 bP are provided on a first side and a second side, respectively, ofthe gate electrode 13P.

Furthermore, sidewall insulating films 13 p are formed on a first and asecond sidewall surface which oppose each other across the gateelectrode 13P. In the element region 11P, a p+ type source region 11 cPand a p+ type drain region 11 dP are disposed outward from the sidewallinsulating films 13 p. On the surface of the source region 11 cP and thedrain region 11 dP, individual silicide layers 11 s are formed.

In the case where the gate electrode 13P is formed using a polysiliconpattern, a silicide layer 14P is disposed also on the gate electrode13P.

Next in the process illustrated in FIG. 1C, a silicon oxide film 15 isformed as an etching stopper film in a thickness of, for example, 10 nmover the structure of FIG. 1B by plasma CVD (chemical vapor deposition)which uses TEOS (tetraethyl orthosilicate) as a basic ingredient. On topof the silicon oxide film 15, an SiN film 16 having a tensile stress of,for example, 1.4 GPa is formed as a tensile stress film in a thicknessof, for example, 80 nm. The formation of the SiN film 16 is achieved bythermal CVD using, for example, silane gas and ammonia gas as basicingredients under the conditions of a pressure of between 0.1 and 400Torr and a substrate temperature of between 500° C. and 700° C.

Next in the process illustrated in FIG. 1D, a silicon oxide film 17 isformed as an etching stopper film in a thickness of, for example, 20 nmover the structure of FIG. 1C by plasma CVD which uses TEOS as a basicingredient, as in the case of the silicon oxide film 15. In the processof FIG. 1E, the silicon oxide film 17 and the SiN film 16 areselectively removed from the element region 11P using a resist patternR1 covering the element region 11N as a mask and using the silicon oxidefilm 15 as an etching stopper.

At this point, in the present embodiment, a resist aperture RA is formedin the resist pattern R1 using exposure data M1 which are used to formthe n-type well 11 nw. With the resist aperture RA, the SiN film 16 isremoved from the p-channel MOS transistor element region.

At the same time in the process of FIG. 1E, a dummy resist aperture RBis formed using dummy exposure data M2 over a part of the elementisolating region 11I outside the element regions 11N and 11P. With theresist aperture RB, the silicon oxide film 17 and the underlying SiNfilm 16 are selectively removed using the silicon oxide film 15 as anetching stopper, at the same time when the procedure using the resistaperture RA is carried out. Herewith, an SiN dummy pattern 16D, on topof which a silicon oxide film pattern 17D is laid, is formed over theelement isolating region 11I in a dummy region 11D.

The etching process of FIG. 1E is achieved by reactive ion etching (RIE)which uses C₄F₈ gas, argon gas and oxygen gas, for example.

Next, in the process illustrated in FIG. 1F, the resist pattern R1 isremoved, and then an SiN film 18 having a compressive stress of, forexample, 1.4 GPa is formed over the structure of FIG. 1E as acompressive stress film in a thickness of, for example, 80 nm. Theformation of the SiN film 18 is achieved by plasma CVD using, forexample, silane gas and ammonia gas as basic ingredients under theconditions of a pressure of between 0.1 and 400 Torr and a substratetemperature of between 400° C. and 700° C.

Next in the process illustrated in FIG. 1G, the silicon oxide film 18 isselectively removed from the element region 11N using a resist patternR2 covering the element region 11P as a mask and using the silicon oxidefilm 17 as an etching stopper.

At this point, in the present embodiment, the resist pattern R2 isformed complementarily to the resist aperture RA using the exposure dataM1 which are used to form the n-type well 11 nw. As a result, the SiNfilm 18 is removed from an outside RC of the resist pattern R2, wherebythe silicon oxide film 17 covering the n-channel MOS transistor isexposed.

The etching process of FIG. 1G is achieved by RIE using CHF₃ gas, Ar gasand oxygen gas.

At the same time in the process of FIG. 1G, a dummy resist pattern R2Dis formed complementarily to the resist aperture RB using the dummyexposure data M2 over a part of the element isolating region 11I outsidethe element regions 11N and 11P. The SiN film 18 is selectively removedusing the dummy resist pattern R2D as a mask and using the silicon oxidefilm 17 as an etching stopper, at the same time when the above-describedprocedure in the region RC is carried out. Herewith, an SiN dummypattern 18D is formed in the dummy region 11D complementarily to the SiNdummy pattern 16D.

Next in the process illustrated in FIG. 1H, the resist patterns R2 andR2D are removed, and an interlayer insulating film 19 is disposed overthe silicon substrate 11 so as to cover the exposed silicon oxide film17 in the element region 11N, cover the exposed SiN film 18 in theelement region 11P and cover the oxide film 17D covering the dummypattern 16D as well as the dummy pattern 18D in the dummy region 11D. Inthe process illustrated in FIG. 1I after planarization is performed bychemical mechanical polishing (CMP), contact plugs 19A, 19B, 19C and 19Dare formed in the interlayer insulating film 19 in such a manner as tobe in contact with the diffusion regions 11 cN, 11 dN, 11 cP and 11 dPvia the individual silicide layers 11 s.

The present embodiment is able to simplify manufacturing processes ofsemiconductor integrated circuit devices in the case where differentsemiconductor integrated circuit devices are manufactured, for example,in the case of manufacturing, after a first device is manufactured, asecond device with the element region 11N having a smaller total area.Specifically, when patterning is performed on the silicon oxide film 17and the underlying tensile stress film 16 by RIE in the process of FIG.1E, as described above, the total etching area of the SiN film 16 overthe semiconductor substrate 11 is maintained constant by increasing thetotal area of the dummy pattern 16D. This eliminates the necessity ofadjusting etching conditions with respect for each device, thussimplifying the manufacturing processes. Similarly, in the case ofmanufacturing, after a first device is manufactured, a second devicewith the element region 11N having a larger total area, the totaletching area of the SiN film 16 over the semiconductor substrate 11 ismaintained constant by reducing the total area of the dummy pattern 16D.

FIG. 2 illustrates the relationship between the etching rate and thearea occupancy of the SiN film pattern formed on a silicon substrate andhaving compressive stress.

Etching is performed by RIE using CHF₃ gas, Ar gas and oxygen gas. Withreference to FIG. 2, if the pattern occupancy over the silicon substrateis 30% or more, a substantially constant etching rate is achievedregardless of the pattern occupancy; however, if the pattern occupancyis less than 30%, the etching rate of the compressive stress filmincreases sharply.

It is considered that, in the case of a tensile stress film,substantially the same relationship exists between the etching rate andthe pattern occupancy. Therefore, in a semiconductor device having aconventional structure in which the n-channel MOS transistor is coveredby a tensile stress film and the p-channel MOS transistor is covered bya compressive stress film, if the total area of the n-channel MOStransistor accounts for 30% or less, for example, or if the total areaof the p-channel MOS transistor accounts for 30% or less, the needarises to optimize the etching process of FIG. 1E or 1G.

On the other hand, in the present embodiment, the dummy patterns 16D and18D are formed on the silicon substrate 11, whereby the ratio of thetotal area of the tensile stress film 16 to the total area of thecompressive stress film 18 on the silicon substrate 11 is controlled tobetween 3/7 or more and 7/3 or less, preferably between 2/3 or more and3/2 or less. Therefore, in either of the above cases (i.e. the case inwhich the total area of the re-channel MOS transistor accounts for 30%or less, and the case in which the total area of the p-channel MOStransistor accounts for 30% or less), the dry etching process of FIG. 1Ecan be performed under identical conditions, and similarly, the dryetching process of FIG. 1G can be performed under identical conditions.

In particular, by maintaining the ratio of the total area of the tensilestress film 16 to the total area of the compressive stress film 18 closeto 1:1, it is possible to prevent the silicon substrate 11 or thesilicon wafer from being distorted.

In the semiconductor integrated circuit device of the presentembodiment, the tensile stress film 16 and the compressive stress film18 are formed complementarily to each other. That is, the surface of thesilicon substrate 11, except for the contact holes, is entirely coveredby either one of the tensile stress film 16 and the compressive stressfilm 18 without substantial overlapping between the tensile stress film16 and the compressive stress film 18. As a result, an extensive convexsurface is absent on the silicon substrate 11, which facilitatesplanarization of the surface of the interlayer insulating film 19 by CMPduring the formation of the interlayer insulating film 19. In the casewhere, due to displacement, the compressive stress film 18 locallyoverlaps the tensile stress film 16, or a gap is present at the junctionarea between the compressive stress film 18 and the tensile stress film16, the present invention tolerates the overlapping part or the gap ifit is comparable in width with a convex structure formed at where thecompressive stress film 18 covers the gate electrode structure.

In the above embodiment, the following formation procedures may beadopted instead. That is, the compressive stress film 18 is firstformed, and the tensile stress film 16 is formed after the compressivestress film 18 is selectively removed from the element region 11N.

FIG. 3 illustrates the structure of such a semiconductor integratedcircuit device in which the compressive stress film 18 is first formedand then the tensile stress film 16 is formed after the compressivestress film 18 is selectively removed from the element region 11N. Inthis case, the tensile stress film 16 laid on top of the compressivestress film 18 is selectively removed from the element region 11P. Thisstructure should be clear from the descriptions given with reference toFIGS. 1A through 1I, and therefore, further explanation is omitted.

Second Embodiment

FIG. 4 illustrates an example of dummy patterns 16D and 18D formed inthe dummy region 11D over the element isolating region 11I. Note that,in FIG. 4, the silicon oxide film 17D disposed on the surface of thedummy pattern 16D is not illustrated.

With reference to FIG. 4, according to the present embodiment, the dummypatterns 18D, each of which is formed of a compressive stress filmmeasuring 3 μm per side, are disposed at intervals of 2 μm with a shiftof 0.5 μm from the nearest dummy patterns 18D in orthogonal directions.

The area ratio of the compressive stress film and the tensile stressfilm can be finely adjusted if the size of each dummy pattern 18D isreduced; however, if the size of the dummy pattern 18D is too small,drawing data becomes large, which incurs in an increase in manufacturingcost of the semiconductor integrated circuit device. Accordingly, it ispreferable to form each dummy pattern 18D measuring about 1 to 5 μm perside. The interval of the dummy patterns 18D is adjusted according tothe area ratio between the compressive stress film and the tensilestress film.

In FIG. 4, it appears that the element isolating region 11I outside thedummy pattern 16D is exposed; however, the figure is illustrated in thismanner only for the intension of indicating that the dummy pattern 16Dis formed over the element isolating region 11I, and the surface of theelement isolating region 11I is not exposed in fact.

According to FIG. 4, the isolated dummy patterns 18D having compressivestress are aligned in the dummy pattern 16D having tensile stress.However, isolated dummy patterns 16D having tensile stress may bealigned in a dummy pattern 18D having compressive stress, as illustratedin FIG. 5.

FIGS. 6 through 8 illustrate examples of dummy patterns formed invarious semiconductor integrated circuit devices.

According to the examples of FIGS. 6 and 7, the strip-shaped elementregions 11P, each including the n-type well 11 nw, and the strip-shapedelement regions 11N, each including the p-type well 11 pw, arealternately aligned, and the isolated dummy patterns 18D are formed,over the element isolating region 11I, complementarily to the dummypattern 16D.

On the other hand, according to the example of FIG. 8, the elementregion 11P including the n-type well 11 nw and the element region 11Nincluding the p-type well 11 pw are separately formed on the siliconsubstrate. In this case also, it can be seen that the dummy patterns 18Dare formed, over the element isolating region 11I, complementarily tothe dummy pattern 16D.

According to the examples of FIGS. 6 through 8, the isolated dummypatterns 18D are formed complementarily to the continuous dummy pattern16D which is formed of a tensile stress film. However, alternatively,the isolated dummy patterns 16D may be formed complementarily to thecontinuous dummy pattern 18D which is formed of a compressive stressfilm.

The following Table 1 concerns various semiconductor integrated circuitdevices, Products A through D, and various test element groups TEG1through TEG4, and illustrates examples of the area occupancy of thecompressive stress film before and after insertion of the dummy patterns18D.

TABLE 1 AREA OCCUPANCY OF COMPRESSIVE STRESS FILM BEFORE DUMMY AFTERDUMMY INSERTION INSERTION PRODUCT A 29.73% 42.27% PRODUCT B 26.00%40.62% PRODUCT C 20.53% 39.78% PRODUCT D 23.92% 38.55% TEG1 10.73%36.17% TEG2 11.61% 37.90% TEG3 17.07% 41.06% TEG4 15.01% 36.82%

With reference to Table 1, as for Products A through D, the areaoccupancy of the compressive stress film before the insertion of thedummy patterns 18D is between 20% and 30%; however, the area occupancyafter the insertion of the dummy patterns 18D increases to between 38%and 42%.

Also, as for TEG1 through TEG4, while the area occupancy of thecompressive stress film before the insertion of the dummy patterns 18Dis between 10% and 15%, the area occupancy after the insertion of thedummy patterns 18D increases to between 36% and 41%.

In conclusion, the present disclosure relates to a semiconductorintegrated circuit device having a structure in which a tensile stressfilm is provided over the re-channel MOS transistor and a compressivestress film is provided over the p-channel MOS transistor. On a part ofthe semiconductor substrate at which neither the n-channel MOStransistor nor the p-channel MOS transistor are formed, the dummypattern of the tensile stress film and the dummy pattern of thecompressive stress film are formed complementarily to each other. Thatis, the surface of the semiconductor substrate is substantially coveredby either one of the tensile stress film and the compressive stressfilm. Accordingly, in the case of manufacturing various semiconductorintegrated circuit devices having different specifications of thep-channel MOS transistor and the re-channel MOS transistor, it is notnecessary to optimize the etching processes conducted when patterning isperformed on the tensile stress film and the compressive stress film,thereby reducing the manufacturing costs of the semiconductor integratedcircuit devices. In addition, the ratio between the total area of thetensile stress film and the total area of the compressive stress film iscontrolled close to 1 by forming the dummy patterns, thereby preventingthe semiconductor substrate from being distorted.

Thus, the embodiments of the present disclosure have been described indetail; however, it should be understood that the present invention isnot limited to the particular embodiments and various changes andmodification may be made to the particular embodiments without departingfrom the scope of the broad scope of the present invention as defined inthe appended claims.

All examples and conditional language recited herein are intended forpedagogical purposes to aid the reader in understanding the inventionand the concepts contributed by the inventor to furthering the art, andare to be construed as being without limitation to such specificallyrecited examples and conditions, nor does the organization of suchexamples in the specification relate to a showing of the superiority orinferiority of the invention. Although the embodiments of the presentdisclosure have been described in detail, it should be understood thatvarious changes, substitutions, and alterations could be made heretowithout departing from the spirit and scope of the invention.

What is claimed is:
 1. A method of manufacturing a semiconductorintegrated circuit device, comprising: forming, over an entire surfaceof a semiconductor substrate, a tensile stress film having tensilestress in such a manner as to cover an n-channel MOS transistor and ap-channel MOS transistor; forming a first resist film over the tensilestress film; performing patterning on the first resist film to form afirst resist aperture in the first resist film in such a manner as tocorrespond to first mask data which define an element region of thep-channel MOS transistor, and form, in an element isolating regionprovided on the semiconductor substrate, a second resist aperture in thefirst resist film in such a manner as to correspond to second mask datawhich define a dummy region; selectively removing the tensile stressfilm from the first resist aperture and the second resist aperture sothat the tensile stress film remaining over the n-channel MOS transistorserves as a tensile stress source pattern and the tensile stress filmremaining in the element isolating region serves as a dummy pattern;removing the first resist film and forming, over the entire surface ofthe semiconductor substrate, a compressive stress film havingcompressive stress; forming a second resist film over the compressivestress film; performing patterning on the second resist film to form afirst resist pattern complementarily to the first resist aperture insuch a manner that the element region of the p-channel MOS transistorremains covered by the second resist film and form a second resistpattern complementarily to the second resist aperture, the first resistpattern corresponding to the first mask data and the second resistpattern corresponding to the second mask data; and performing patterningon the compressive stress film using the first resist pattern and thesecond resist pattern as masks so that the compressive stress filmremaining over the p-channel MOS transistor serves as a compressivestress source pattern and the compressive stress film remaining in theelement isolating region serves as a complementary dummy pattern whichis complementary to the dummy pattern.
 2. The method as claimed in claim1, wherein a ratio between a total area of the dummy pattern and a totalarea of the complementary dummy pattern is in a range of 3/7 to 7/3. 3.A method of manufacturing a semiconductor integrated circuit device,comprising: forming, over an entire surface of a semiconductorsubstrate, a compressive stress film having compressive stress in such amanner as to cover an n-channel MOS transistor and a p-channel MOStransistor; forming a first resist film over the compressive stressfilm; performing patterning on the first resist film to form a firstresist aperture in the first resist film in such a manner as tocorrespond to first mask data which define an element region of then-channel MOS transistor, and form, in an element isolating regionprovided on the semiconductor substrate, a second resist aperture in thefirst resist film in such a manner as to correspond to second mask datawhich define a dummy region; selectively removing the compressive stressfilm from the first resist aperture and the second resist aperture sothat the compressive stress film remaining over the p-channel MOStransistor serves as a compressive stress source pattern and thecompressive stress film remaining in the element isolating region servesas a dummy pattern; removing the first resist film and forming, over theentire surface of the semiconductor substrate, a tensile stress filmhaving tensile stress; forming a second resist film over the tensilestress film; performing patterning on the second resist film to form afirst resist pattern complementarily to the first resist aperture insuch a manner that the element region of the re-channel MOS transistorremains covered by the second resist film and form a second resistpattern complementarily to the second resist aperture, the first resistpattern corresponding to the first mask data and the second resistpattern corresponding to the second mask data; and performing patterningon the tensile stress film using the first resist pattern and the secondresist pattern as masks so that the tensile stress film remaining overthe re-channel MOS transistor serves as a tensile stress source patternand the tensile stress film remaining in the element isolating regionserves as a complementary dummy pattern which is complementary to thedummy pattern.
 4. The method as claimed in claim 3, wherein a ratiobetween a total area of the dummy pattern and a total area of thecomplementary dummy pattern is in a range of 3/7 to 7/3.